Envelope Sizes
4 indexed entriesPart of Office & Print Supplies.
Items
C4
A C4 envelope measures 229 x 324 millimeters, sized to hold an A4 sheet completely flat and unfolded. It's the standard ISO 269 envelope for mailing full-size documents without folding.
C5
A C5 envelope measures 162 x 229 millimeters, exactly half the size of a C4 envelope and sized to hold an A4 sheet folded once in half, or an A5 sheet flat.
C6
A C6 envelope measures 114 x 162 millimeters, exactly half the size of a C5 envelope and sized to hold an A4 sheet folded twice (into quarters), or an A6 sheet flat.
DL
A DL envelope measures 110 x 220 millimeters, sized to hold an A4 sheet folded into thirds -- the standard shape for window envelopes and everyday business correspondence across most of the world outside North America.